Home Electronics Review

Aged Plastic Becomes Hard And Brittle In Fluke 85 Series 3 Multimeter Causing Structural Failure

noreply@blogger.com (Unknown) — Mon, 26 Jul 2021 13:10:00 +0000

After years of use, the plastic in my Fluke 85 multi meter becomes hard and brittle. The 1st to go is the function selection switch as the plastic making it up just crumble with force is applied. Next the battery cover, the clamps for the LCD modules. If the case of the Fluke 85 has been made with bakelite like in the old electronics it may have lasted longer, or some modern materials like fibre glass or epoxy reinforced fabric.

Fluke could have use better materials for the case. The plastic here becomes brittle and hard with age, leading to structural failure in the multimeter, even though the electronics are functioning very well.

The electronics are still performing well and outlast the plastics. Should be possible to rewire the function selection switch into some individual switches for function selection. Do watch this space.

Inside a Philips LED Bulb

noreply@blogger.com (Unknown) — Mon, 26 Jul 2021 12:58:00 +0000

Encapsulated LED Driver Electronic. The fuse seems to have blown,

A aluminium shell surround the electronics module. Acting as heat sink for the electronics and also the leds.

Review of LightAir ionFlow 50 Surface Air Purifier : Is it worth the price?

noreply@blogger.com (Unknown) — Fri, 22 Jan 2021 13:44:00 +0000

Bought a LightAir IonFlow 50 Surface Air Purifier cheaply online. Here is what inside. This is the first time I am using a IonFlow air purifier. After almost a day of operation, there seems to be very little dust collected. Also because this is a used IonFlow, the corona discharge needles are rusted and there is reduced ionization. It does operate very silently as there is no fan. Although LightAir call the IonFlow a air purifier, it actually operates more like a negative ions generator. The use of a high voltage positive collector cylinder, neutralized any ozone produce. So it is quite a good negative ions generator. Negative ions actually does neutralized pathogens in the air and is good for human heath. The chief draw back for this relatively expensive air purifier is that the corona needles use to generate the negative ions are easily rusted from prolonged use. This will over time make the IonFlow being ineffective and almost become useless. LightAir could have gold plated the corona needles or use some other corrosion resistance metal or metal alloy for the corona needles.

Although every air purifier maker will say they have proprietary technology etc, the electronic high voltage generator circuit is very much common engineering know how. LightAir right to charge a high price for this air purifier is the industrial design for an ionizing air purifier. The IonFlow technology is based very much on the know principles of negative ions being accelerated and moving towards a positive charge object, in this case the cylinder attached to the low part of the machine. It does create an ionic field around the machine, in this case with the enhanced corona discharge needles, a 360 degrees negative ion zone up to 1 meter around the machine. The positively charged collector can effectively collect very fine particles, larger particles will simply fall off or swirl around in the air. As small particles of PM2.5 and below are most harmful as they then to go deeper into the lungs, this can be a good thing.

The main assembly in the LightAir IonFlow 50 Surface Air Purifer.

This is where all the electronics are housed.

The core electronics module is the high voltage generator, seen here as a large encapsulated module.

The negative high voltage is connected to 3 corona discharge needles at the top of the assembly. The positive high voltage is connected to a spring loaded clip which then connects to the aluminum cylinder.

A look at the circuitry of the high voltage generator can be found at https://fccid.io/YJ550-STAND-MODEL/Internal-Photos/Internal-Photos-1316399

The corona discharge needles for electrons. These ionized the air and particles in the air with a negative charge,

The blue LED module and 12V DC power inlet

The corona needles are quite rusty due to long use, resulting in poor electrons emission.

Considering the price of LightAir IonFlow 50 Surface Air Purifier, LightAir could have gold plated the corona needles to prolong its service life.

See later in the post how the strength and reach of the electrons is increased by first cleaning the corona needles and then attaching carbon fibers emitters to them.

The aluminum cylinder is connected to positive high voltage and collects negative charge particles. These are very fine particles, like soot and traffic emissions, large particles do not seems to collected, either they are not charge negative enough or they just fall to ground around the IonFlow 50 Surface Air Purifier.

The Rusted Bearing In Motor Of A OSIM OS-6800 iEcologi Vaccum Cleaner

noreply@blogger.com (Unknown) — Mon, 02 Nov 2020 08:16:00 +0000

However efficient the filtering is, dust and moisture will get suck into the motor of a vaccuum cleaner and over time can cause corrosion. The motor bearing is corroded, resulting in the motor running very noisy and maybe even over heating and drawing excessive current.

The particular bearing is remove from the motor of a OSIM iEcologu Vacuum Cleaner with water filter

Actually if the rest of the vacuum cleaner is in serviceable condition, it may be worth the while to remove the motor to change the rusted bearing.

What Is Inside A OSIM OS-6800 iEcologi Vaccum Cleaner

noreply@blogger.com (Unknown) — Sat, 31 Oct 2020 12:59:00 +0000

This OSIM iEcologi was retired due to a excessively noisy motor. As it turns out the bearing at the impeller end is severely rusted.

Despite the water filtration and mechanical filter quite a bit of dirt do managed to get suck into the motor where some of it will probably get expelled into the air again,

The AC power plug developed a loose connection on the Live terminal, giving intermittent power connection.

The water tank, the boiler ( top ), the motor sits below the water tank together with the water pump which pump water into the boiler

The water boiler with the heater attached at the bottom

The carbon brushes for the motor, still in fair wear condition.

Water pump to meter water into the boiler

The electronic control board to monitor steam pressure and boiler

The motor disassembled

Safety warning label Hot steam danger for pets and people

The 4 castor wheels will be useful for upcycling into wheeled platform for shifting things around

Inside a 1.2 Volt Nickel Cadmium Battery. How it is made.

noreply@blogger.com (Unknown) — Sat, 26 Sep 2020 02:57:00 +0000

Inside a used and dead nickel cadmium battery. NiCd battery are actually obsolete. They can be leaky and the chemicals are very corrosive for the electronics that they powered.

Inside a step tracker. Well made with 55mAH Lithium ion battery

noreply@blogger.com (Unknown) — Sat, 26 Sep 2020 02:55:00 +0000

Simple step tracker with bluetooth connection. Tiny lithium polymer battery with 55mAH capacity. New step trackers are wireless charge, this model is charge via USB

Inside microwave oven high voltage capacitor

noreply@blogger.com (Unknown) — Sat, 26 Sep 2020 02:39:00 +0000

Dismantle a high voltage capacitor from a microwave oven. It is filled with some oil, hopefully is PCB free, has as strong odor, very difficult to wash off completely if you get some on your hand, need multiple washing with soap, alcohol hand wash seems to help more. The 10M ohm safety resistor is salvage for use in a DIY high voltage probe. The safety resistor will discharge the capacitor after the oven is switch off. The voltage can be as high as 4 KV. A dangerous voltage if you accidentally touch the capacitor or the connecting wires during servicing or dismantling. So always switch off the microwave oven before opening the cabinet for servicing.

Corroded Alkaline 1.5V Battery -

noreply@blogger.com (Unknown) — Sat, 26 Sep 2020 02:27:00 +0000

The zinc case of the battery which is also the negative terminal of the battery is corroded, probably the zinc case is too thin to start with. Many expensive battery operated electronic equipment has been damage due to leaking chemicals from batteries.

Gas igniter in cooker hob

noreply@blogger.com (Unknown) — Sat, 26 Sep 2020 02:22:00 +0000

Recover this gas igniter from a very greasy gas cooker hob. The electronics circuit are very well coated with resin to prevent moisture and oil penetration. The casing of the igniter is very greasy, so that grease do migrate to the underside of some hob. The white plastic casing is a little brittle due to prolong operation in a hot environment and age. Yes plastic due degrade but into smaller pieces and when they get into the environment bad things happen. Use less plastic in your daily living. This igniter has 3 separate high voltage windings, each for one cooking point.

Sanyo 2N-600AE 2.4V Ni-Cad Battery. Nickel Cadmium Battery Corrosion and Leak

noreply@blogger.com (Unknown) — Sat, 04 Jan 2020 02:07:00 +0000

SANYO 2N-600E 2.4 Volt Nickel Cadmium. Fully discharged and leaking.
Ni-Cad batteries are a common cause of equipment faulure due to battery leakage damaging the battery terminals and also the internal circuits as the liquide leaking seeps into the equipment.

Ni-Cad battery contains cadmium can should not be discarded into the normal waste bin.

Corroded positive terminal of the battery

SANYO makes anything from battery to refrigerators to radios to televisions to light bulbs to semicnonductores.

Each Ni-Cad battery nominal voltage is 1.2 volt to get 2.4 Volt 2 Ni-Cad batteries is connected in series and packaged as one.

USB Negative ION Generator - Has mild negative ions emanating.

noreply@blogger.com (Unknown) — Wed, 01 Jan 2020 05:17:00 +0000

SMD components side of the PCB.

The tiny SMD transistor is running hot after a while, which is typical of a single transistor oscillator circuit, not too sure if the tiny SMD capacitors and diodes stand well to the supposedly high voltage created by the 3 stage voltage multiplier circuit.

Upper side of the PCB.
Showing the carbon brush negative ions emitter, a tiny voltage step up transformer, a green LED for power on, a filter cap for the 5V DC Input via the USB connector.

USB Negative Ion Generator compare to a Teflon Tube

USB Negative ION Generator vs Teflon Tube on a simple DIY negative static electricity detector

noreply@blogger.com (Unknown) — Wed, 01 Jan 2020 04:45:00 +0000

A teeny winny USB negative ion generator vs a Teflon tube. Verdict: Teflon tube win.

The USB negative ion generator dont seems to be generating enough negative to active the LED.

The negative static electricity detector is build using a P channel MOSFET, IRF9620, a 100 ohm resistor and a red LED, power by a 9V DC battery.

The Teflon tube hold the negative charge very well and will continue to lit up the LED even after a fews hours after charging by rubbing it with a cotton cloth.

Inside A Energiser 9V Battery - It actually have 6 tiny batteries inside, smaller than the AAA size

noreply@blogger.com (Unknown) — Mon, 30 Dec 2019 01:08:00 +0000

They really made batteries in the USA!

Corrosion on the negative terminal of the 9V Battery

Leakage and corrosion on the positive terminal of each 1.5V tiny AAA battery.

Vintage AIWA 14400 BPS Fax Modem Review Tear Down

noreply@blogger.com (Unknown) — Tue, 24 Dec 2019 02:16:00 +0000

Trusty vintage fax modem. Built almost to military specs. Cost USD350 in those days. The LCD still in good condition, most LCD will developed a black patch on the reflector when aged. Still able to power on nicely with a warm yellow glow in the LCD display. But need to scrap it as it is no longer energy efficient. Fax modems are now commonly found in scanner printers and they are all build into a large integration circuit chip, except for the analog phone circuit which still need bulky signal transformer, surge and lightning suppressors etc.

Underside of the PCB withTexas Instruments integrated circuits IC chips SN74 series

EEPROM with firmware for image encoding decoding

Probably CPU chips or PLA Programmable Logic Arrays

The analogue phone circuitry

Power supply unit detached from the main PCB

EMI EMF aluminium shield sheet

Checking Out A Novita Wine Cooler NWC-12 That Is Not Cooling Well

noreply@blogger.com (Unknown) — Mon, 10 Jun 2019 13:45:00 +0000

Took home a Novita Wine Cooler from someone who wish to give it a second chance. It was not cooling to a temperature low enough for chilling wine. After powering up for an hour the temperature was only 22C.

Open the back cover to have a look:

Turns out the a possible reason for the insufficient cooling is this pile of dirt covering the cooling fins of the heat radiator.

Took it to the wash room and flush the cooling fins to remove the dirt and also wash out the cooling fan.

Power it on again and after 2 hours is able to cool the wine cabinet interior to 17 degree C.

Essentially this is a dependable wine chiller.

A better build quality would be to add a user washable air filter on the outside. This would help keep the cooling fins cleaner for longer and the user can easily wash out the filter without removing the back cover and removing the cooling fan to uncover all those pile of dirt that accumulate over years of use.

Apart from that the cooler works fine, except for a missing segment in the LED temperature display. And the touch buttons will not response after a while of power on and need a power off and on again sequence to be responsive again.

Try to set the chiller to 11 degree C, but it done seems to be reaching there even after a few hours of operation.

Took out the cooling unit and some corrosion and dirt on the cool side of the cooling unit.

Also there dont seems to be any casket around the opening where the cool side of the cooling unit

will be place into the cabinet interior. This may cause cool air to leak around the edges.

The opening where the cool side of the Peltier Cooler
will extend into the cabinet

Cool Side Of the Peltier Cooling Unit.
This portion extend into the chiller cabinet via an opening at the back.

Cool Side Of The Peltier Cooling Unit
The black piece below the cooling fins is the Peltier Cooler

Why Canon Document Scanner AC Power Adapter Is A Consumable Item

noreply@blogger.com (Unknown) — Fri, 05 Aug 2016 06:06:00 +0000

A friend brought me a AC adapter use to power a Canon Document Scanner, asking if it is possible to repair it. It has been in used for only six months and is not dead. A replacement is not available from Canon as Cannon classify the ac power adapter as a consumable.

So electronics has advance to such a stage that a ac power adapter can be consumed by providing clean DC power to a document scanner? Thumbs up for e-waste recycling.

I decided to take a look inside the adapater to see where it has worn out due to fair wear and tear.

There is not much to see except for 3 burned resistors and a burnt diode.

Interestingly the heat sink for the power transistor or FET seems to be on the lighter side.

A multimeter check both in circuit and after removal of the transistor/FET show a short inside the device measuring at about 5 ohms.

Which brings me to the idea that this ac adapter fails because of insufficient heat sinking due to the thin copper plate.

Moreover on closer inspection, the transistor/FET is not affixed to the heat sink via a layer of silicone heat sink paste as was practice in most quality electronics.

So I think this ac adapter fails because of overheating of the transistor/FET due to:

1. Too small a heat sink
2. No silicone heat sink compound use to ensure close thermal conduction between the tranistor/FET and the thin copper plate.

Dead Canon Document Scanner AC Power Adapter

Immediately obvious is the thin copper plate use as heat sinks in this Canon AC Power Adapter

Burnt resistors feeding the switching circuit, give clue to a shorted switching FET.

No silicone grease between the FET and copper heat sink to ensure good thermal conductivity.

FET did not have a close contact to the copper surface of the heat sink, note the tiny air gap

So the Canon document scanner ac power adapter is a "consumable" because it is not design to last as long as the scanner itself, heat stress will wear out the ac adapter just like too much usage will wear out the paper feed rollers, as heat stress is dependent on usage time and also ambient temperature yes the ac adapter will be consumed after pro long use. So if it burns out before warranty time no you wont get a free replacement but you have to buy a new one at a 150 Singapore dollars.

Why Canon Document Scanner AC Power Adapter Is A Consumable Item

noreply@blogger.com (Unknown) — Fri, 05 Aug 2016 06:06:00 +0000

A friend brought me a AC adapter use to power a Cannon Document Scanner, asking if it is possible to repair it. It has been in used for only six months and is not dead. A replacement is not available from Cannon as Cannon classify the ac power adapter as a consumable.

So electronics has advance to such a stage that a ac power adapter can be consumed by providing clean DC power to a document scanner?

I decided to take a look inside the adapater to see where it has worn out due to fair wear and tear.

There is not much to see except for 3 burned resistors and a burnt diode.

Interestingly the heat sink for the power transistor or FET seems to be on the lighter side.

A multimeter check both in circuit and after removal of the transistor/FET show a short inside the device measuring at about 5 ohms.

Which brings me to the idea that this ac adapter fails because of insufficient heat sinking due to the thin copper plate.

Moreover on closer inspection, the transistor/FET is not affixed to the heat sink via a layer of silicone heat sink paste as was practice in most quality electronics.

So I think this ac adapter fails because of overheating of the transistor/FET due to:

1. Too small a heat sink
2. No silicone heat sink compound use to ensure close thermal conduction between the tranistor/FET and the thin copper plate.

Dead Cannon Document Scanner AC Power Adapter

Immediately obvious is the thin copper plate use as heat sinks in this Cannon AC Power Adapter

Burnt resistors feeding the switching circuit, give clue to a shorted switching FET.

No silicone grease between the FET and copper heat sink to ensure good thermal conductivity.

FET did not have a close contact to the copper surface of the heat sink, note the tiny air gap

A Look Inside A 5 Watt 230V AC LED Bulb Suitable For Replacing CFL Light Bulbs

noreply@blogger.com (Unknown) — Sun, 24 Jul 2016 03:33:00 +0000

I bought this 5 Watt LED as a early adopter in LED home lighting. As a early design this bulb does not offer good omnidirectional lighting compare to the newer designs from Philips, Osram, GE and scores others. As can be seen this particular LED light bulb can be quite expensive to manufacture considering the amount of aluminium need in the housing not to mention the safety issue with so much exposed metal in a consumer LED light bulb operating at 230V AC.

I am particularly worry about the electrical safety of this 230V AC LED bulb as there is too much expose metal use to cool the LED chip.

I have currently replaced this which a Philips 13.5 Watt LED Bulb with E27 socket.

Large Finned Housing Offer Little Contact With Main Body
Of LED Itself

The LED Driver electronics module is wrapped in wax paper and
place inside the finned aluminium housing.

There is a remote possibility of a short circuit to the bulb housing,
so I decided to stop using this type of LED bulb.

I planned to reused the LED bulb in a home made LED touch.
The LED driver is reused by installing it inside a adapter casing
which I then used to power G11 type LED bulb I bought on eBay

Connections Of Actual Components In A Fuzzy Logic National Rice Cooker SR-MM18N

noreply@blogger.com (Unknown) — Sat, 22 Feb 2014 08:05:00 +0000

So this is how all the components in the Fuzzy Logic National Rice Cooker SR-MM18N are connected. Connecting wires are silicon or teflon insulation for high heat environment.

Inside a Fuzzy Logic National Rice Cooker SR-MM18N

noreply@blogger.com (Unknown) — Wed, 19 Feb 2014 08:20:00 +0000

Inside a Fuzzy Logic National Rice Cooker SR-MM18N.

My trusty 10 year rice cooker seems to be taking a bit too long to cook the rice. Not so sure what the problem. Probably some alignment needed for the electronics circuit inside. So I took it apart to have a look.

There really quite a handful of parts in the rice cooker. This are probably hand assembled together making it quite a pricey rice cooker.

Some pics to appreciate the beauty and sophistication of a modern rice cooker controlled by a computer chip!.

What really missing is some intelligent software to calibrate the heating again due to aging components instead of having to open the unit and make adjustment with a variable resistor.

Keep warm heater in lid.
Thinking about it, living in sunny Singapore, maybe

I dont need a keep warm function in the rice cooker.

Wonder what the loose piece of brown board is for.
Found it there after opening the National rice cooker.

Beautiful cast aluminoum heating plate with
embeded 800 Watt 230VAC heating element.

Sensor to detect presence of rice pot and

temperature of rice in pot.

Once the batery is flat the clock stops

working and you lost the timer cooking

function. Call this design obsolescence.

Computer controlled rice cooker.

It use to be you just need a pot

and a open fire to cook your rice.

The computer make it very safe you wont burn your rice you
just need to press the correct button on the control panel.
You need to understand man machine interface. But who doesnt now a days.

Kenwood KD-600 Turntable What's Inside

noreply@blogger.com (Unknown) — Sun, 22 Jul 2012 01:33:00 +0000

Just took apart a Kenwood KD-600 quartz phase locked direct drive turntable, It is a well built turntable, except for a weakness in the choice of a fibre board for the base cover which wear out with age.

The electronics are still in good condition. The motor turns nicely. But the speed at 33 RPM cannot be locked.

The electronics requires a regulated +15VDC and a unregulated +25VDC input fed via the 3 terminal connector.

Inside The Vitacon Thyristor 828S Camera Flash

noreply@blogger.com (Unknown) — Thu, 19 Jul 2012 08:28:00 +0000

Here is the Vitacon camera flash disassembled. A pretty sophisticated design with multiple thyristor controls, use to quench the flash and trigger the flash. Need 4 AA size battery giving 6 volts. A powerful camera flash gun. This is probably obsolete now with LED camera flash and low light digital camera and video cameras.

Vitacon Thyristor 828S Camera Flash

1990s 1 Megapixel Digital Camera Webcam Obrite

noreply@blogger.com (Unknown) — Thu, 19 Jul 2012 08:22:00 +0000

This is an early 1990s digital camera made by Obrite, a relatively unknown brand. Consumer electronics has became a commodity such that anyone with enough cash can get a electronics contract manufacturer to make any thing they like and stick their own brand on it.

This camera is about 1 Mega pixels organised as 640 x 360 pixels. It has a USB connection and needs 2 AA size battery for operation. When connected to the PC using the USB it doubles up as a web cam.

Here is some pictures of the inside components of the digital camera.

Obrite 1 Megapixel Digital Camera And Webcam.

Make In Singapore AC 230V TO 15 V AC Step Down Power Transformer

noreply@blogger.com (Unknown) — Thu, 12 Jul 2012 13:57:00 +0000

A Made In Singapore AC low voltage power transformer. This is typical of the early industrialisation SME manufacturing in Singapore in the 1970s and 1980s. These transformers are probably made for local consumption in the building industry, the local factories and offices powering equipment like PA system, fire alarms, smoke detectors etc.

This transformer meets just basic electrical safety standards. The AC high voltage 230VAC winding is wound on the same bobbin as the low voltage AC and is insulated from it by heavy wax paper. Tighter safety regulations like UL electrical standards will requires the two windings to be separated on different halves of the plastic bobbin.

I have decided to srape it and recover the copper and iron. This produces about 300 grams of copper wire and almost 700 grams of scrap iron.

I recover about 300 grams of scrap copper wire from
this ac transformer.

Add caption